I see HD Australia have given ANZA Motorcycles the see you later message.

[Crasherfromwayback]

Awesome, thanks heaps, the info and experience shared freely on this forum is priceless to us less knowledgeable types..

I'll tell ya a crazy thing that I'd never have believed had I not seen it myself on the dyno. When using ex rap (yeah I know!), you can move the torque curve up and down the rev range a wee bit depending on how long you rap the headers.

[old slider]

I'll tell ya a crazy thing that I'd never have believed had I not seen it myself on the dyno. When using ex rap (yeah I know!), you can move the torque curve up and down the rev range a wee bit depending on how long you rap the headers.

Amazing things exhausts, Ron Grant back in the late 70s managed to pull some more boogey out of my old XS650 playing with the exhaust system, mind you the Kenny Roberts bits he sourced also helped. lol

I was surprised how much longer and quicker the revs were on the FB after the simple Hi flow air filter and re tune were done.

[husaberg]

I'll tell ya a crazy thing that I'd never have believed had I not seen it myself on the dyno. When using ex rap (yeah I know!), you can move the torque curve up and down the rev range a wee bit depending on how long you rap the headers.

The heat and subsequent heat loss of the pipe effects the heat of exhaust gasses, ergo it effects the length at which it resonates.
modern two strokes use both heavily retarded timming and fine control of electric powerjets after peak power to put additional heat into the exhaust, there by making it respond as if the tunned length was actually shorter.
They also use carbon sheilds to prevent exposed areas of chamber being cooled at high speed.
https://www.kiwibiker.co.nz/forums/a...5&d=1413875766

[awayatc]

Anyone on the forum installed the short 2into 1 Hi output ?

Did have Python 2 in 1 on mine.
Looked great..
More groundclearance cornering.
Sounds was nice and deep. But to loud for my liking.
Oh yes it did make it run a bit better....(seat of pants)

[old slider]

Did have Python 2 in 1 on mine.
Looked great..
More groundclearance cornering.
Sounds was nice and deep. But to loud for my liking.
Oh yes it did make it run a bit better....(seat of pants)

Thanks awayatc, looks like there is an optional quiet baffle that can be purchased with the V & H exhaust, I currently struggle to hear my bike with helmet on at highway speeds, mind you the wife says I never listen.

[riffer]

The heat and subsequent heat loss of the pipe effects the heat of exhaust gasses, ergo it effects the length at which it resonates.
modern two strokes use both heavily retarded timming and fine control of electric powerjets after peak power to put additional heat into the exhaust, there by making it respond as if the tunned length was actually shorter.
They also use carbon sheilds to prevent exposed areas of chamber being cooled at high speed.
https://www.kiwibiker.co.nz/forums/a...5&d=1413875766

You know, until your post, I was about to tell crasherfromwayback his post was the biggest load of shite I've ever heard. Now I'm gonna have to think about that.

[Crasherfromwayback]

You know, until your post, I was about to tell crasherfromwayback his post was the biggest load of shite I've ever heard. Now I'm gonna have to think about that.

You'd be most welcome to. But you'd be calling me a liar, and I'd tell you to get fucked. One thing Dynos can't do mate...is lie. And only one of us is a mechanic by trade...

[old slider]

They're great. I wouldn't use anything other than a 2-1 on them. All the std systems have cross over pipes , they run far nicer than one with two sep exhausts. Performance Research was just what WMCC used to call stuff they'de made and tested on their Dyno.

Thanks Guys for all the responses and sharing of knowledge and experience.

The 2 into 1 Hi output exhaust is on its way with some new seals. Big thanks to Pete, (motorcycle Alley) another good bugger who went out of his way to give me good advice and service.

Been a big month for the old girl with front and rear suspension upgrades happening and a new exhaust system. I had no intention of doing any upgrades when I got it just over a year ago, Bikes are funny bloody things, no wonder they get given girls names.

[Crasherfromwayback]

. Big thanks to Pete, (motorcycle Alley)

He'd have to be a good cunt with a name like that.

[old slider]

He'd have to be a good cunt with a name like that.

Lol, yes it seems to be the name of a few good buggers.

[husaberg]

You know, until your post, I was about to tell crasherfromwayback his post was the biggest load of shite I've ever heard. Now I'm gonna have to think about that.

The gains and variation on a Harley are of course less than a two stroke, but it is a real phenomenon.
All you are doing is increasing of decreasing the temp and speed of the exhaust gasses. Hence the effective tuned length of the pipe.
Thats why all decent exhaust pipe calculators use the exhaust gas speed.

[Katman]

It's the same theory behind the HPC coating of exhausts.

[husaberg]

It's the same theory behind the HPC coating of exhausts.

Not really, the ceramic coating is to keep the heat within the exhaust rather than a variable manipulation of an exhaust tuned length. The response of the coating only effects the tunned length which is irrelevant as they are application specific.
2 stroke expansion chambers require different lengths depending on the gauge or the material ie mild steel or SS or TI. But this is factored in at design stage
HPC like coatings do have advatages when used on internal components such as combustion chambers. as they prevent heat disipation and mitigation which (additionally) also helps burn off deposits
But it’s mostly to look pretty and be durable on exhausts.
It does have an advantage of not transferring the heat to the engine ancillaries though which i actually the real reason Nascars actually used heat wrap, mainly to stop the alternator cooking and other heat soak to engine and carb etc.

[Katman]

Not really, the ceramic coating is to keep the heat within the exhaust rather than a variable manipulation of an exhaust tuned length.

Of course the coating doesn't provide variable manipulation, you fucking moron. Once it's on, it's on.

The theory is the same though in that it increases the exhaust gas temperature and therefore the exhaust gas velocity.

[old slider]

Nice to see the ANZA Harley boys working out of City Honda in Palmerston North.

Nothing better than talking to guys who know their Brand and when leaving your bike knowing it is in good hands.

Big thanks as well to Crasherfromwayback for giving me the heads up on a couple of things that I needed to research.

great site this Kiwi biker.